The present invention relates generally to a marking device and particularly to marking devices for use with measuring tape to mark a desired distance measured by the measuring tape.
Measuring tapes are used in a variety of environments for measuring material such as in the construction industry, distances in a floor layout, the manufacture various products and in the household. Once the tape measures a desired distance, a mark is placed on the material measured to establish the distance measured. It is important to make sure that the mark indicates the desired distance. If the mark is made with a pencil, considerable time is spent making sure that the point of the pencil is placed at exactly the measured distance. If the person making the mark is at an angle with respect to the material being marked or the tape is spaced above the surface of the material to be marked, a parallax problem can create inaccurate placing of the mark. When that mark is then used to cut or otherwise shape the material, that cut or shaping of the material is inaccurate and may not be usable.
Known tape measures typically have a flexible measuring tape resiliently coiled within a housing. The tape is normally printed with measuring marks for measuring distances.
Various devices have been developed for incorporating a marker for use with a coiled flexible measuring tape. Agostinacci, U.S. Pat. No. 4,965,941, discloses a combination marker and tape measure. The marker is manually movable to a marking position and is biased toward a retracted position by a spring. The flexible measuring tape is biased toward its coiled position with a separate spring device. The marker has an integral liquid reservoir for supplying ink for making the mark.
Another marking device and is disclosed in Kaufman, U.S. Pat. No. 5,416,978, and provides a marker device which is actuated to make a mark or a series of marks by lugs formed on the measuring tape. Other tape measuring devices are provided by Elliott, U.S. Pat. No. 4,439,927, Ruffer, U.S. Pat. No. 5,815,939, and Ljungberg, U.S. Pat. No. 4,651,429.
It is desirable to provide a marking device that accurately places a mark on a workpiece, particularly by avoiding a parallax problem with the operator of the marking device. If the person making the mark is at an angle with respect to the material being marked or the tape is spaced from the surface of the material to be marked, a parallax problem can create inaccurate placing of a mark.
It is also desirable to provide a marking device having a simplified design which utilizes the spring urging the tape to the coiled position to also urge the marker from the marking position to the retracted position. A simplified design also allows for easily made components which are assembled to provide a marking device.
It is also desirable to be able to accurately mark the same distance a number of times. For example, when cutting a piece of lumber occasionally the same distance must be marked from an edge a series of times so that a straight line can be cut. If those marks are not the same distance, a straight line will not be cut and the material will not be usable.
It is also desirable to be able to make a series of accurate marks in a minimum amount of time. By increasing the speed of making accurate marks, the labor costs are decreased and layout times are reduced. Increased speed also results from a marker being readily available. For example, if a marker, such as a pencil, is used, frequently the pencil cannot be found and valuable time is spent looking for it. It is also desirable to provide a marking device that can be actuated with the same hand as that holding the tape.
Another desirable feature is to provide a marking device that can be mounted on existing measuring tapes. It is also desirable to provide a marking device that is simple in construction to reduce the complexity and cost of manufacturing. It is also desirable to provide a marking device that is compact and light in weight.
The present invention provides the above described desirable features with improved marking device for use with a measuring tape to mark a desired distance measured by the tape.
The present invention provides a marking device for use with a measuring tape extendable from a coiled position to mark a desired distance measured by the tape which includes a housing having an outer surface with an actuation aperture and a marking aperture therethrough. An actuation member is provided having an exterior portion extending through the actuation aperture and outwardly therefrom. The actuation member is movably mounted to the housing in a slot and is movable between a retracted position and the marking position. A slot is provided in the actuation member to receive a pin attached to the housing for guiding the movement of the actuation member between the retracted and the marking position. A marker holder is also provided with a marker attached thereto.
The measuring tape has measuring marks printed thereon for measuring distances and is resiliently coiled around a rotational axis about which the tape is coiled. To measure a distance, the flexible tape is partially uncoiled and extended a sufficient amount to indicate the distance measured. That distance can then be marked with the marker, on the material to be marked positioned directly under marker.
The marker holder and its marker are movable from a retracted position to a marking position by activation of the actuation member. When in the marking position, the marker extends through the marking aperture to place a mark on the surface of a workpiece. The marking aperture is in alignment with the desired measuring mark on the measuring tape so that when the actuation member is activated a mark is accurately made on the surface of a workpiece.
The marking device has a guide device to guide the marker holder upon movement of the marker between the retracted in marking positions. The guide device includes cooperating slots and pins that guide the marker from the retracted position and the marking position. The marking device has an inker for providing ink to the marker would when a marker is moved from the retracted position to the marking position.
When the marker is in the retracted position, the marker is adjacent the inker. As the marker is moved from the retracted position to the marking position, it is guided across the inker to supply ink to the marker. After picking up ink from the inker, the marker moves in a vertical direction through the marker aperture to mark the distance measured. To guide such movement of the marker, the guide device includes a pair of spaced pins secured to the marker holder which are received by a pair of slots in the marking device housing. The slot receiving the pin closest to the marker is configured to guide the marker across the inker as it is moved from the retracted to the marking position and then in a vertical direction to make a mark on the workpiece.
The marking device and present invention also provides a biasing device connected to the marker holder to urge the marker holder towards the retracted position. When the actuation member is manually depressed, the force exerted thereon overcomes the biasing force of the biasing device and moves the marker from the retracted to the marking position. When the actuation member is deactivated or released, the force of the biasing device moves the marker holder and the actuation member back to the retracted position.
The biasing device of the present invention includes a biasing arm and a spring connected to the biasing arm. The biasing arm is connected to the marker holder to urge the marker holder towards the retracted position. The spring is also connected to the measuring tape to urge the tape to the coiled position while allowing movement of the tape to an extended position in which the measure markings can be viewed. The spring is wound around its rotational axis and is adapted to urge the tape to its coiled position around the same rotational axis.
Other desirable features and advantages of the present invention will become apparent from a study of the following description and the accompanying drawings which are illustrative of the invention.